Size and weight is a big decision factor when you are trying to find the ideal camera for your needs.
In this section, We are going to illustrate Canon G1 X III and Canon M3 side-by-side from the front, back and top in their relative dimensions. Canon G1 X III has external dimensions of 115 x 78 x 51 mm (4.53 x 3.07 x 2.01″) and weighs 399 g (0.88 lb / 14.07 oz) (including batteries). Canon M3 has external dimensions of 111 x 68 x 44 mm (4.37 x 2.68 x 1.73″) and weighs 366 g (0.81 lb / 12.91 oz) (including batteries).
Below you can see the front view size comparison of Canon G1 X III and Canon M3. Canon M3 is clearly the smaller of the two cameras. Its body is 4mm narrower, 10mm shorter and 7mm thinner than Canon G1 X III. As you can tell, actually this is not a fair size comparison since Canon G1 X III has a built-in lens but Canon M3 doesn't. Once you put a lens on M3, its thickness will increase significantly.
Here is the back view size comparison of Canon G1 X III and Canon M3.
Now lets look at the top view comparison of Canon G1 X III and Canon M3.
Weight is another important factor especially when deciding on a camera that you want to carry with you all day.
Canon M3 is 33g lighter than the Canon G1 X III but we don't think this will make a significant difference.
Again, this comparison may not be very useful in real life as we are comparing the weight of a camera with a built-in lens to the body-only weight of an interchangeable lens camera. Once you put a lens on M3, the total kit will weigh much higher.
With its weather sealed body, we believe that G1 X III has a big advantage over M3 which doesn't provide any kind of environmental sealing.
LCD Screen Size and Features
Canon G1 X III and Canon M3's LCD screens has the same diagonal size of 3".
Canon M3 features a Tilting only screen
which is mostly only good for shooting from waist or over the head levels. On the other hand, Canon G1 X III sports a Fully Articulated screen
which is more flexible and useful especially for taking Selfie shots and video.